Co-Infusion of Umbilical Cord Blood and Haploidentical CD34+ Cells Following Nonmyeloablative Conditioning as Treatment for Severe Aplastic Anemia and MDS Associated With Severe Neutropenia Refractory to Immunosuppressive Therapy
Severe aplastic anemia (SAA) and myelodysplastic syndrome (MDS) are life-threatening bone
marrow disorders. For SAA patients, long term survival can be achieved with
immunosuppressive treatment. However, of those patients treated with immunosuppressive
therapy, one quarter to one third will not respond, and about 50 percent of responders will
relapse.
Allogeneic bone marrow transplantation from either HLA-matched sibling or matched unrelated
donor cures about 70 percent of patients with SAA and 30-60 percent of patients with MDS.
Unfortunately, most patients with these disorders are not suitable candidates for
hematopoietic stem cell transplantation (HSCT) due to advanced age or lack of a
histocompatible donor. For such patients, transplantation using unrelated cord blood (UCB)
has been shown to be a reasonable alternative transplant strategy. The advantage to UCB
transplant is the ease and rapidity of availability, requirement of less than perfect HLA
match, and lower rates of graft versus host disease compared to mismatched bone marrow or
peripheral blood stem cell transplants. The major disadvantage of UCB transplantation in
adults is the limited number of nucleated cells contained within the cord unit resulting in
prolonged neutropenia and failure of engraftment which contributes to infection and
transplant related mortality (TRM). In order to harness the advantage of UCB availability
and to overcome the disadvantage of delayed neutrophil recovery, we propose to test whether
co-administration of unrelated umbilical cord blood and a relatively low number of highly
purified haploidentical peripheral blood CD34+ cells from a related donor might promote
rapid engraftment and reduce TRM secondary to prolonged neutropenia associated with
conventional UCBT.
This research protocol is therefore designed to evaluate the safety and effectiveness of
co-infusion of unrelated umbilical cord blood and haploidentical CD34 plus cells from a
related donor following nonmyeloablative conditioning for neutropenic patients with SAA or
MDS that has proven to be refractory to medical therapy. Subjects will receive a novel
non-myeloablative immunosuppressive conditioning regimen of cyclophosphamide, fludarabine,
horse ATG and one dose of total body irradiation (200cGy) followed by an infusion of the
allografts. The haploidentical stem cell product will be T-cell depleted and enriched for
CD34 plus cells using the Miltenyi CliniMacs system. To reduce TRM secondary to prolonged
neutropenia associated with conventional UCB transplantation, haploidentical CD34+ stem
cells will be co-infused with a single UCB unit (serologically matched at greater than or
equal to 4/6 HLA loci).
The primary endpoint is donor engraftment by day 42 (defined as an ANC of greater than 500
from either the haplo donor, the cord, or both combined). Secondary endpoints will include
standard transplant outcome variables such as non-hematological toxicities, incidence and
severity of acute and chronic GVHD, and relapse of disease. We will also evaluate ANC
recovery (ANC greater than 500 cells/microl) at day 22, and 100 day and 200 day treatment
related mortality (TRM) of this novel transplant approach. Health related quality of life
will also be assessed pre-transplant 30 and 100 days poste transplant, and every 6 months
until 5 years post transplant.
Interventional
Allocation: Non-Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
Day 42 cord engraftment
Day 42
No
Richard W Childs, M.D.
Principal Investigator
National Heart, Lung, and Blood Institute (NHLBI)
United States: Federal Government
080046
NCT00604201
January 2008
December 2015
Name | Location |
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National Institutes of Health Clinical Center, 9000 Rockville Pike | Bethesda, Maryland 20892 |